Underground-telegraph line



(No Model.)

D. BROOKS UNDERGROUND TLBGRAPH LINE. No. 254,268. Patented Feb. 28,1882.

NNN ff Q, ,Q

. and @funk/ 95M? La www w ffm LW UNITED STATES PATENT OEEIQE.

DAVID BROOKS, OF PHILADELPHIA, PENNSYLVANIA.

UNDERGROUND-TELEGRAPH LINE.

SPECIFICATION forming part of Letters Patent No. 254,268, dated February 28, 1882.

Application tiled November 7, 1881. (No model.)

To all whom it may concern:

Be it known that I, DAVID Baoorrs, a'etizen of the United States, and a resident of Philadelphia, Pennsylvania, have invented certain Improvements in Underground-Telegraph Lilies, et' which the followingis a specification.

My invention relates to improvements in the undergrouIul-telegraph system for which I obtained Letters Patent of the United States No. 210,986, dated December 17,1878; andthe object of my present invention is to prevent the escape of the insulating-duid at. the ter- Ininal stations. rPhis object I attain by forcing paraffne, rosin, or equivalent material under pressure around the cotton-covered Wires in the pipe near the .end of the pipe.

In the accompanying drawings, Figure ll is a diagram showing a terminal station, and Fig. 2 an enlarged sectional view ot'a terminal pipe.

A represents the horizontal sections of pipe or tubing containing' the usual cable or strand ot' coveredlwires to be insulated in oil, and B represents a vertical branch carrying the wires above ground at the terminalstation. Ihe wires in the sections of pipe are preferably the usual cotton-covered wires,which, however. do not extend out ofthe pipe at the terminal station, but at some little dista-nce within the vertical branch B-say at the point x-nre connected up to corresponding gutta-perchacovered or iudiaruliber-covered wires extending out ofthe top of the pipe to the desired points.

In orderto prevent the insulatingoil or other iluid, which is introduced in to the tubing under pressure between the terminals, from escaping out of the pipe at the terminal stations, I introduee para-dine, resin, beeswax, ozocerite, or similar plastic insulating material into each terminal pipe and compress it around the wires, the plastic material preferably extending from a point near where the rubber-covered wires are connected to the cotton-covered wires to a short distance along the horizontal portion ofthe tubing.

For introducing the paraffine or similar material after the wires are introduced, I provide one or more short branch pipes, D D', preferably one branch7 D, on a vertical portion of the tubing, and another branch, D', on a horizontal portion of the tubing near the bend. Each 0I' these branches is internally screwthreaded for the reception ot a corresponding screw-plug, E E', so that after a quantity of paraiijne or similar material has been introduced through the branch it can be forced into the pipe by turning these screw-plugs, and then more ot the plastic material introduced and compressed until it is practically impossible to compress it any further, when all the crevices will have been thoroughly filled up and the pipe effectually plugged, so as to prevent the oil, which is introduced at a point between the terminals, from oozing out at any of the vertical branches B. Each screw-plug E E has a squared head for the application of a key, F, Fig. 2, to get the required pressure.

I claim as my invention- The mode herein described of preventing the escape of insulating-duid from the terminal pipes of undergrouiid-telegraph lines-that is, which consists in compressingparafne or similar material around the wires in the pipe near the end of the pipe.

In testimony whereof I have signed my name to this spccilication in the presence ot' two subscribing witnesses.

DAVID BROOKS. 

